• The US is sending advanced missile defence systems and 100 troops to Israel amid escalating conflict.
• The THAAD system aims to bolster Israel’s defence against potential Iranian missile attacks.
• Biden’s decision to deploy THAAD before Israel’s planned assault on Iran raises concerns about US casualties.

The United States is sending one of its most advanced missile defence systems and about 100 US troops to Israel, deepening US involvement in the escalating war in the Middle East amid US expectations of an imminent Israeli assault on Iran.

The mission marks the first significant deployment of US troops to Israel since the war in Gaza began and comes just three weeks before the US presidential election, in which US involvement in the conflict has been a polarising issue on the campaign trail. US officials have been encouraging Israel to avoid targeting Iran’s nuclear, oil and gas sites out of fear that it could spark an even larger escalation that upends the global economy.

The deployment of the Terminal High Altitude Area Defence missile system, or THAAD, is the latest indication that the US expects the Israeli assault to be “so comprehensive that the Iranians will have to respond”, said Aaron David Miller, a Middle East expert who has advised multiple Republican and Democratic administrations. The THAAD deployment adds to the more than 50,000 tons of armaments and military equipment the US has sent Israel since the start of the war last October, according to Israel’s Defence Ministry.

Israel’s Defence Minister, Yoav Gallant, has promised a devastating attack against Tehran in response to its ballistic missile barrage against Israel on October 1. “Our strike will be powerful, precise, and above all – surprising. They will not understand what happened and how it happened,” Gallant said last week.

The Iranian assault, which followed Israel’s assassination of high-level Iranian, Hamas and Hezbollah officials, failed to inflict significant damage as a result of US and Israeli efforts to shoot down the projectiles. No deaths occurred within Israel’s internationally recognised borders; one Palestinian man was killed in the occupied West Bank.

The barrage, however, demonstrated that Israel’s sophisticated missile defence system can be overwhelmed, allowing scores of missiles to hit Israeli soil.

“The THAAD battery will augment Israel’s integrated air defence system,” said Pentagon spokesman Pat Ryder. “This action underscores the United States’ ironclad commitment to the defence of Israel, and to defend Americans in Israel, from any further ballistic missile attacks by Iran.”

Both Vice-President Kamala Harris and former President Donald Trump have vowed to forcefully defend Israel, while expressing support for a swift end to the fighting. The conflict has deeply divided the Democratic Party, with young voters and Arab Americans criticising Harris for not calling for restrictions on US arms to Israel in response to the killing of more than 42,000 people in Gaza and blockages of humanitarian aid.

Republicans, on the other hand, have attacked the Biden administration for criticising Israel’s military tactics following Hamas’s October 7, 2023, attack that killed 1200 people and took more than 250 hostage.

Despite numerous disagreements between President Joe Biden and Israeli Prime Minister Benjamin Netanyahu over the course of the year-long war against Hamas, the President’s decision to deliver the THAAD system before Israel’s attack represents another example of his willingness to trust Netanyahu and give him the benefit of the doubt.

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“Once this battery is in place and Israel enjoys the protection of American air defenders, what incentive does Netanyahu have to keep his word and not strike the sensitive targets he promised to avoid?” asked Harrison Mann, a former US Army officer who served as an analyst at the Defence Intelligence Agency.

The THAAD system is specifically designed to shoot down ballistic missiles. The ground-based system doesn’t have any warheads and isn’t used to strike buildings or conduct offensive attacks. Rather, the system only counters incoming short-, medium- and intermediate-range ballistic missiles.

The shipment, which will be delivered at an unknown date, is the latest example of Biden using “carrots” rather than sticks to induce Israel into less aggressive behaviour, said Mann.

On Friday, the Biden administration imposed economic sanctions on Iran’s petroleum industry, targeting Tehran’s fleet of tankers, in the hopes that such action would lessen Israel’s desire to strike Iran’s energy assets, which could prompt Tehran to target oil facilities owned by Washington’s Arab allies.

The decision to place more US troops in Israel amid an impending attack increases the risk of US casualties – a scenario that could drag the US even further into the widening conflict, said Miller.

“If Iranian missiles hit a US soldier or pro-Iranian militias in Iraq or Syria kill or wound US personnel, there’s a high probability that the US would take kinetic action against Iran,” said Miller.

The US will deploy THAAD missiles to Israel, deepening the US involvement in the war. Photo / Getty Images

Earlier this year, the US military deployed a pier to deliver humanitarian aid to Gaza, but the Biden administration decided against putting troops on the ground for the mission out of safety concerns for US forces and fears of being dragged further into the conflict.

Mann said the risk to US soldiers who will crew the THAAD system is clear.

“Those soldiers will be operating from Israeli military bases, which Iran already demonstrated the will and capability to strike, at a time when additional Iranian strikes are expected imminently,” he said. “Even if we make the unreasonably optimistic assumption that this THAAD battery can defeat any and all missiles headed its way, the Israeli military cannot guarantee the safety of these troops from drones, which have successfully penetrated Israeli bases in the past.”

Each THAAD battery includes at least six truck-mounted launchers that carry up to eight missiles each. The system is widely sought after, particularly by Ukraine, which is routinely under siege from Russian ballistic missiles.

The US military deployed the system to the Middle East last year after the October 7 attack on Israel, Ryder said, and in 2019 as part of a training event.

Israel has other anti-missile defences, including its Iron Dome, Arrow and David’s Sling systems.